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Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!) A035480 Pseudoperfect numbers (A005835) that are not practical (second definition, A007620). 2 102, 114, 138, 174, 186, 222, 246, 258, 282, 318, 350, 354, 366, 372, 402, 426, 438, 444, 474, 490, 492, 498, 516, 534, 550, 564, 572, 582, 606, 618, 636, 642, 650, 654, 678, 708, 732, 738, 748, 762, 770, 774, 786, 804, 822, 834, 846, 852, 876, 894, 906, 910, 940, 942, 945, 948, 954, 978, 996, 1002 (list; graph; refs; listen; history; text; internal format) OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..1000 MATHEMATICA Cases[ A005835, q_/; (Count[ CoefficientList[ Series[ Times@@( (1+z^#)& /@ Divisors[ q ] ), {z, 0, q} ], z ], 0 ]>0) ] CROSSREFS Numbers in A005835 but not in A007620. Cf. A007621. Sequence in context: A031413 A127665 A097037 * A181986 A107838 A095637 Adjacent sequences: A035477 A035478 A035479 * A035481 A035482 A035483 KEYWORD nonn AUTHOR Wouter Meeussen EXTENSIONS Corrected by David W. Wilson. STATUS approved

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Last modified August 18 23:41 EDT 2024. Contains 375284 sequences. (Running on oeis4.)